Will anxiety medicines cause memory loss?

My sister is worried about not having a job. She has attended many interviews, but she couldn't acquire one. She is worried and tensed about this. She is not having a tight sleep. She used to read books or watch movies all the night to spend her time. This late night sleep is badly affecting her physical health too. She is a person who likes to spend her time with friends than family. Nowadays she is avoiding her friends and not even attending their calls. Last day, her friends came and compelled her to go for an outing. But she hesitated to go with them. They compelled again, but she got angry and shouted at them and after that she apologized to them. Her friends are really supportive and caring, so they didn't mind it. We all have tried to console her, but our words are not enough to change her. It is clear that she is dealing with some anxiety. So we are planning to consult an anxiety disorder therapist in Toronto. I heard that the medicines for anxiety will cause memory loss. Do we need to concern over this? Help me with your replies.